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Des scientifique fabriquent la vie sans ADN !

Des scientifique fabriquent la vie sans ADN !
Scientists trying to create artificial life generally work under the assumption that life must be carbon-based, but what if a living thing could be made from another element? One British researcher may have proven that theory, potentially rewriting the book of life. Lee Cronin of the University of Glasgow has created lifelike cells from metal — a feat few believed feasible. The discovery opens the door to the possibility that there may be life forms in the universe not based on carbon, reports New Scientist. Even more remarkable, Cronin has hinted that the metal-based cells may be replicating themselves and evolving. "I am 100 percent positive that we can get evolution to work outside organic biology," he said. The high-functioning "cells" that Cronin has built are constructed from large polyoxometalates derived from a range of metal atoms, like tungsten. The metallic bubbles are certainly cell-like, but are they actually alive? The early results have been encouraging.

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Microbes Living in Tiny Water Droplets Help Break Down Oil It doesn’t take much to keep oil-consuming microbes happy and working. Researchers have discovered communities of microorganisms that live in the tiniest droplets of water suspended in natural tar lakes, where they actively break down oil from the inside out. These thriving microhabitats need very little water to support them, and they could be harnessed for cleaning up disastrous spills.

Material Science Madness: Crazy Metal Melts in Your Hand There is an incredible metal that shatters like glass, melts in a human hand, attacks other metals but is non-toxic to humans, and acts like an alien life form when exposed to sulfuric acid and dichromate solution. It sounds too amazing to be true, but gallium is an absolutely real chemical element that’s found in some of the gadgets we use every day. But perhaps more interestingly, there are a ton of insane experiments scientists like to do with gallium. The Body’s Ecosystem The human body is teeming with microbes—trillions of them. The commensal bacteria and fungi that live on and inside us outnumber our own cells 10-to-1, and the viruses that teem inside those cells and ours may add another order of magnitude. Genetic analyses of samples from different body regions have revealed the diverse and dynamic communities of microbes that inhabit not just the gut and areas directly exposed to the outside world, but also parts of the body that were long assumed to be microbe-free, such as the placenta, which turns out to harbor bacteria most closely akin to those in the mouth. The mouth microbiome is also suspected of influencing bacterial communities in the lungs. Researchers are also examining the basic biology of the microbiomes of the penis, the vagina, and the skin. THE BODY'S MICROBIOMES: Genomic surveys of the body’s bacterial, fungal, and viral inhabitants are revealing diverse microbial communities that likely play key roles in human health and disease.

Aerographite Is the World's Lightest Material, Is a Total Airhead and Kind of Weird The last time we looked at ultra-lightweight materials, we were thoroughly impressed by a spongy, metallic micro-lattice that held a density of 0.9 milligrams per cubic centimeter (mg/cc). Now, a team of German scientists from the Technical University of Hamburg and University of Kiel has developed a new carbon-nanotube-based material called Aerographite that’s four times lighter at 0.2mg/cc. As you might have surmised from Aerographite’s name, it’s a material made of mostly air--99.99 percent, to be exact--along with carbon nanotubes. This Microbe's Hair is Actually a Nanowire for Powering Itself When researchers first looked at the long tendrils grown by “electric bacteria” called Shewanella, they thought it was just common bacterial hair (or pili) for sensing surfaces and connecting to other bacteria. Now, an examination of their structure reveals that they’re actually nanowires that can conduct electricity. The work was published in Proceedings of the National Academy of Sciences this week. “The pili idea was the strongest hypothesis, but we were always cautious because the exact composition and structure were very elusive. Then we solved the experimental challenges and the hard data took us in a completely different direction. I have never been happier about being wrong,” says Moh El-Naggar at the University of Southern California in a news release.

évolution ADN dans l'histoire Image Source : Wiki Commons Spectrum of human genetic diversity today is vastly different from only 200 to 400 generations ago A study dating the age of more than 1 million single-letter variations in the human DNA code reveals that most of these mutations are of recent origin, evolutionarily speaking. These kinds of mutations change one nucleotide – an A, C, T or G – in the DNA sequence. Over 86 percent of the harmful protein-coding mutations of this type arose in humans just during the past 5,000 to 10,000 years.

LF Special Report: 10 Futuristic Materials Lifeboat Foundation Safeguarding Humanity Skip to content Switch to White Special Report 10 Futuristic Materials Are Your Bacteria Making You Fat? If you reach for that tasty piece of chocolate, even though you are trying to lose weight, are you doing it out of your own volition? Or are you actually being controlled by the bacteria in your gut? This is the question posed in BioEssays by Dr Carlo Maley of the University of California San Francisco. “Bacteria within the gut are manipulative,” said Marley.

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